Steam boiler



Feb. 3, 1931. D. s. JACOBUS STEAM BOILER Filed Dec. 18, 1,923 3 Sheets-Sheet 1 lmlwi b if INVENTOR.

6 P, M ATTORNEYS. I

Feb. 3, 1931. D. s. JA'coBus 1,790,750

STEAM BOILER Filed Dec. 18, 1925 '5 Sheets-Sheet 2 INVENTOR; flhx falw BY awe; M

ATTORNEYS.

D. s. JACOBUS 1,790,750

STEAM BOILER Filed Dec. 18 1925' 3 Sheets-Sheet 5 Feb. 3.; 1931.

M ATTORNEYS Mi .B )6

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attented Feb. 23, 1931 um ran STATES,

PATENT OFFICE I DAVID S. JACOBUS, F JERSEY CITY, NEW JERSEY, ASSIGNOR, BY MESNE ASSIGNMENTS, TOQEULLER LEHIGH COMPANY, A CORPORATION OE DELAWARE STEAM BOILER Application filed December 18, 1923. Serial No. 681,350.

My present invention relates to improvements in Water tube boilers which will be best understood from the following description and the annexed drawings of an illustrative embodiment of my invention, in which Fig. 1 is a side elevation in section of the illustrative embodiment; Fig. 2 is an enlarged view of a detail; Fig. 3 is a section on line 3-3 of Fig. 2; Figs. 4 and 5 are enlarged sections on lines 4-4 and 5.-5, re-

. spectively, of Fig. 1; Fig. 6 is a section on line 66 of Fig. 1, part of the rear wall being broken awa to show the slag screen tube arrangement; ig. 7 is. a section similar to Fig. 1, showing a modification; Fig. 8 is a section on line ab of Fig. 7; Fig. 9 is an enlarged perspcctiveof a part of'Fig. 7 showing another modification, and Fig. 10 is a section on line 10-l0 of Fig. 9.

Like reference characters indicate like parts in the several views.

In the illustrative embodiment, the boiler has a steam and water drum 10 connected to water tubes by means of uptake headers 1'1 and 12 and downtake headers 13 and 14, the tubes being divided into an upper bank 15 anda lower bank 16, separated to produce a chamber therebetween, in which there is a superhcater 17. The boiler is provided with a baffle 18 forming a continuation of a short horizontal baffle 19 above the tubes 16, the superheater headers 20 and 21 forming a part of this baffle, and also a bafile 22 across the upper bank 15, the gases passing upwardly over the tubes 16, the superheater 17 and over the baffle 22, and thence downward to a gas outlet through the nipples 23 into an economizer 24, through which they pass downwardly to a gas outlet at the bottom.

Beneath the boiler is a furnace chamber 25 which preferably is made relatively high In the burning of certain fuels, particularly with some forms of combustion apparatus, there is a tendency to form slag par ticles which rise with the hot gases and are caused to adhere to the water'tubes, so that the gas passages therebetween become closed in a relatively short time. In order to obviate the difficulties of such slag formation,

I provide one or more rows of water tubes extending-across the furnace in the path of the hot gases,and preferably at a relatively considerable distance below the lowerlanes before they reach the relatively closely spaced water tubes.

In Fig. 1, I have shown such a slag screen as made up of a pair of rows of water tubes 26 and 27, such tubes being relatively widely spaced across the boiler compared with the,

spacing of the tubes 15 and 16, as shown in Fig. 6, and preferably with the tubes of the row 26 staggered somewhat at least in relation-to the tubes 27, partly for mechanical reasons, because in the construction shown.

in Fig. 1, these tubes enter a common header at substantially the same line, and partly for operative reasons, in order to more effectively prevent the laning of the gases.

The lowermost ends of the tubes 26 are entered into a crossheader 28 outside of the rear furnace wall 29, and the corresponding ends of the tubes 27 are entered into. a cross header 30, also outside of the wall 29. The front ends of the tubes 26 and 27 are entered into across header 31 outside of the front wall 32 of the furnace chamber. The header 28 is connected tothe drum 10 by downtake pipes or tubes 33 spaced along the header 28 i and correspondingly along the drum 10, and

the header .30 is connected by uptake pipes or tubes 34, the number of downtake tubes 33 being preferably less than the uptake tubes 34 and these two sets of tubes being staggered, as best shown in Fig. 2, so that the tubes of one set may cross the plane of the tubes of another set. Preferably each tube 33, 34 is bent at some point in its length to permit the tube to yield if its two ends tend to be moved toward each other. The row of tubes 27 has a baflie 36 extending part way along its length and the row of tubes 26 has a similar baffle, formed partly of tiles 35 resting on the tubes and partly of a row of tiles 35' surrounding the tubes for a purpose to be described more fully hereinafter. Each of the battles 35 and I 36 forms a contraction for the flow area from the furnace adjacent to the slag screen tubes. Such contraction, combined with the space between the slag screen tubes and the upper water tubes, promotes mixing of gases by permitting them to re-expand after leaving the contraction in a space above the slag screen tubes. 1

The tubes 26 and 27 extend through relatively large openings in the furnace walls 29 and 32 arranged to permit headers 28, and 31 to shift relatively to each other and to the drum 10 without injuring the walls. These relatively large 0 enings may be made substantially gas-tig t by a pair of plates 29* surrounding the tube and free to move vertically in'slideways formed by plates 29*, as best shown in Figs. 2 and 3. The openings in the furnace walls may be rovided with a metal plate closure arrange tofit over the opening, this closure preferably having a.

door 29 by which access may be had through the opening to clean the slag deposited on the tubes 26 and 27.

The hot gases from the grate 25 rise through the tubes 26 and 27, being diverted by the baffles and 33, and then pass between the boiler tubes 15 and 16 and out between the nipples 23. In passing through the tiibes 26 and 27, the water therein, of course, is heated, and since these rows are connected in series, the water and steam'will rise through the tubes 26, then into the header 31, then into the tubes 27 and the uptake tubes 34 into the steam and water drum. Similarly, water will pass from the steam and water drum 10 through the downtake tubes 33 to the header 28. This arrangement provides a circulation through the slag screen tubes entirely independent of the circulation through the water tubes 15 and 13 and their respective uptake and downtake headers into the steam and water drum 10. This permits a very rapid circulation through the tubes 23 and 27 which, of course, would be required because these tubes are subjected to the hottest gases. hot slag particles striking the tubes and the bafiles oi the slag screen will be cooled suiiiciently to adhere thereto, but since these two rows of tubes are widely weaves spaced, there would be no bridging between the tubes of the two rows, and, moreover, as the slag accumulates in a plastic condition, it will-drop off the tubes and the bafies thereon when a considerable quantity has accumulated thereon. The slag accumulating on the tubes 26 and the baflie 35 will be prevented from flowing down the tubes to the furnace wall 29 by the large tiles 35' which extend below the tubes 26, such slag being stopped by these tiles and caused to drip into the bed of fuel on the grate 25 By the time the gases have reached the lower set of tubes 16, the greater quantity ofslag-producing material will have been removed from the gases, so that there will be little or no deposit on the tubes 16. Moreover, by spacing the rows 26 and 27 a considerable distance below the bank 16, any laning, due to the partial cooling of some of the gases by these tubes, will be prevented, because the space above the row 27 will be suificient to permit the gases to remix and to enter between the tubes 16 substantially uniformly heated instead of having lanes of relatively hot and relatively cool gases,as would be the case if the rows 26 and 27 were c ose to the tubes 16.

The casing 3'i' is preferably arranged to cover the tubes 33 and 34 and may be provided with an opening 38 by which access may be had to these tubes as well as to the downtake headers of the boiler. A soot pocket 39 is shown having an access door 40 through which access may be had also to the rear of the boiler as Well as to the soot pocket itself.

By providing the batlies 35 and 36 on the positing any solid products carried by the gases upon the upper side of the baffie 35 and which may be cleaned therefrom by means of the removable access doors located immediately above the lower ends of the tubes 26 in Fig. 1. Similarly, the gases in passing 'Erom the space between the two rows of tubes and 2'? are again compelled to change their dirce tion in passing to the combustion chamber above the upper row of slag screen tubes 2?. At the same time, the gases above the upper row of tubes 27 spread out into the space above said tubes, and, as the flow area through this some is larger than that over the tubes, the ocity of the gases is changed, as well as their c" notion, thereby promoting the deposition solid particles carried by the gases on ie upper side of the battle 36, from which t tee removals A above l access doors inuncdiately .nds the tubes as illus- .27 7 1 i ir a. v y can lihemse no cleaned in i slag screen tubes 26 and 27, causes a thorough mingling of the gases, thereby promoting combusition while causing deposition of the solid products carried thereby.

In Fig. 7, I have shown a modification in which a single row of tubes is used in the slag screen, the tubes 27 being connected at the high end to a cross header 30 into which passages through the tubes 27.

The furnace is shown fired with an underfeed'forcedraft stoker 25", the combustion chamber having the front wall 32and the rear wall 29'. In this form, the gases, as

before, pass upward through the slag screen tubes 27', in which there is a circulation the tubes 34.

through the downcomer pipes 33, the tubes 27 and the uptake pipes 34',-'which is independent of the circulation through the tubes I5 and 16 with their headers. The tubes 27 may be spaced acrossthe furnace at desired intervals and preferably willbe more closely spaced than when aiplurality of rows of tubes are used in the slag screen. The tubes 27 pass through openings in the frontand rear furnace walls, arranged to be maintained closed notwithstanding possible vertical motion of the tubes 27 in relation to such walls, which closures may be of the form described and illustrated in connection with Fig. 1.

A soot pocket 39 has an access door 40 by which access may be had not only to the soot pocket, but also to the tubes 34 and the downtake headers, the casing 37' extending over Instead of the arrangementof tiles shown in Fig. 8, the arrangement shown in Figs. 9 and 10 may be used. In this form, each tube 27' will be surrounded by cylindrical tile across the furnace chamber, suchtile being conveniently made up of two semi-cylindrical sections 41 and 42 having internalgrooves engaging the flanges of metallic members 43.

This arrangement is described more in detail. in the United States Letters Patent No.

If desired, such encircling tile may be used for a portion only of the tubes 27', the flat tile 27 being used for the remainder, or such encircling tile may be used for only a portion of the length of the tubes 27'. v

While I have shown my 'invention as applied to a horizontally inclinedwater tube boiler, it will 'be understood that it may be applied to other types, in which it isdesirable to screen out the slag particles before the relatively closely spaced and usually staggered water tubes are reached.

I claim: 1. A water tube boiler having a bank of water tubes spaced across the bank, a drum and connections between the ends of the tubes and the drum to form a circulatory system through said water tubes, a furnace to sup ply hot gases to said water tubes, the distance between the source of heated furnace gases and the entrance to the bank of tubes being sufficient to permit substantially completetherefrom, the gas flow spaces between the tubes in said rows of slag screen tubes being greater than the gas flow spaces between the tubes in said bank, and connections between the ends of the tubes in said rows and the drum to form a circulatory system through the tubes of said rows independent of the circulation through said bank, substantially all of the combustion air being admitted below saidrows'of slag screen tubes.

2. A water tube boiler having a bank of water tubes spaced across the bank, a drum combustion before the gases enter said bank,

a plurality of rows of slag screen tubes extending across the furnace between said source and saidbankof tubes, and over which the gases flow before reaching said bank, means associated with said slag screen tubes constructed and arranged to cause a change in the direction of the gases andadapted to receive deposit therefrom, the gas flow spaces between the tubes in said rows of slag screen tubes being greater than the gas flow spaces between the tubes in said bank and with the tubes in each of said rows in staggered relation to the tubes in an adjacent row of said slag screen tubes, and connections betweeu the ends of the tubes in said rows and the drum to form a circulatory system through the tubes of said row independent of the circulation thro'ugh said bank, substantially all of the combustion air being'admitted behorizontally-inclined water tubes spaced across the bank, a drum and connections between the ends of the tubes of said bank and said drum, a furnace beneath said bank, the

distance between the source of heatedgases and the entrance to said bank being sufficiently high to permit substantially complete combustion before the gases enter said bank,

across the bank, a drum and connections between the ends of the tubes of said bank and said drum, a furnace beneath said bank, the

, distance between the source of heated gases and the entrance to said bank being sufficiently high to permit substantially complete combustion before the gases enter said bank, a plurality of rows of horizontally-inclined slag screen tubes extending across the furnace beneath said bank and widely spaced therefrom and from said source to provide a large combustion space above and below said rows, a bafiieextending along a portionof one of the rows of said slag screen tubes and forming a contraction for the flow of furnace gases'and connections between the ends of the tubes in said rows and the boiler to form a circulatory system through the tubes of said row independent of the oircu1ation through said bank.

5 A water tube boiler having a bank of horizontally-inclined water tubes spaced across the bank, a drum and connections between the ends of the tubes of said bank and said drum, a furnace beneath said bank, the

distance between the source of heated gases and the entrance to said bank being sufliciently high to permit substantially complete combustion before the gases enter said bank, a plurality, of alternately oppositely inclined rows of slag screen tubes extending across the furnace between said source and said bank, with the high ends of the tubes in one row connected to the low ends of the tubes in the next higher row, connections between the drum and the-high ends of the topmost row and the-low ends of the lowermost row, and a baffle on each row of slag screen tubes extending from the lowermost ends of the tubes inwardly partially across the furnace chamber.

6. A water tube boiler having a' bank of horizontally-inclined water tubes spaced across the bank, a drum and connections between the ends of the tubes of said bank and said drum, a furnace beneath said bank, a set of slag screen tubes extending across the i eogrse furnace beneath the bank and across and through the path of the gases flowing to said bank, and widely spaced therefrom and from the source of the heated furnace gases, said set comprising a plurality of alternately oppositely inclined rows of tubes, headers outside the furnace and connecting the ends of the tubes in each row and the high ends of one row of tubes and the low ends of the adjacent row of tubes being connected by said headers, a baflie extending along a portion of the lowermost tubes of said set of slag screen tubes, and connections between the drum and the uppermost and the lowermost headers.

7. In combination, a furnace, a boiler having a set of Water tubes adapted to be contacted by the furnace gases and connections between the ends of said water tubes to form a circulatory systemfchrough said Water tubes, a second set of horizontally inclined water tubes extending across and through. the path of the furnace gases to be contacted by the gases before the gases contact with the first set of tubes, said second set of tubes extending through the furnace walls, refractory tile surrounding each tube of said .second set at the lowermost ends thereof adjacent the furnace wall and inside thereof, and connections between the ends of said second set of tubes and the boiler to form a circulatory system through said second set of tubes independent of the circulation' through said first set of tubes.

8. In combination, a furnace, a boiler having a set of water tubes. adapted to be contacted bythe furnace gases and connections between the ends of said water tubes to form a .circulatory system through said water tubes, a second set of horizontally inclined water tubes arranged in a plurality of rows alternately oppositely inclined and extending across and through the path of the furnace gases to be contacted by the gases before the gases contact with the first set of tubes, baflles on each row'of tubes of said second set and extending from the lowermost ends of the tubes inwardly partially across the furnace chamber, connections between the high ends of the tubes in one row and the low ends of the tubes in an adjacent row, and connections between the drum and the high Tends of the tubes in the uppermost row and the low ends of the tubes in the lowermost row.

9. In combination, a furnace, a boiler having a set of water tubes adapted to be contacted by the furnace gases and connections between the ends of said water tubes to form a circulatory system through said water tubes, a second set of, horizontally in clined water tubes arranged in a plurality of rows alternately oppositely inclined and extending across the furnace, and through the walls thereof to be contacted by the gases before the gases contact with the first set of tubes, bafiles on each row of tubes extending from the lowermost ends of the tubes in-' wardly partially across the furnace chamber, the baflle on the lowermost row of said second set of water tubes having an en-;

tending beneath and contacting with the lower sides of the tubes, said tile being spaced from the furnace wall through which the lower ends of said tubes extend, and the gases flowing through said inclined tubes above said tile.

11. In combination, a furnace, a row of inclined water tubes extendin through the furnace walls and across the, mace, tile on the lower ends of the tubes and extending beneath and contactin with the lower sides of the tubes, said tile eing spaced from the furnace wall throu h which the lower ends of said tubes extend, and a bafiie resting on the said tubes at their lower ends and ex- 7 tending from the furnace wall inwardly partially across the furnace.

, 12. In combination, a furnace, a row of inclined water tubes extending across the furnace, headers connected to the ends of said tubes and tile on the lower ends of the tubes and extending beneath and contacting with the lower sides of the tubes, said tile being spaced from the adjacent'header, and the gases flowing through said inclined tubes above said tile.

13. In combination, a furnace, a row of inclined water tubes extending through the "furnace walls and across the furnace, and

tile on the lower ends of the tubes, a portion of said tile extending beneath and contacting with the lower sides of the tubes, said portion being spaced from the adjacent furnace wall and constituting a drip-forming portion, and the.- gases flowing through said inclined tubes above said tile.

14. A watertube boiler having a bank of horizontally-inclined water tubes spaced across the bank, a drum and connections between the ends of the tubes of said bank and said drum, a furnace beneathsaid bank, the distance between the sourceofjY-heated gases and the entrance to said bank being suficiently high to permit substantially complete combustion before the gases'enter said bank, a row of horizontally-inclined slag screen tubes'extending across the furnace beneath said bank and widely spaced therefrom and from said source to provide a large combustion space above and below said .row, a baflle extending over a portion only of said slag screen tubes, and connections between the ends of the tubes in said row and the drum to provide a circulation-therethrough indepenlrient of the circulation through the main 15. A water tube boiler having a bank of horizontally-inclined water tubes spaced across the bank, a drum and connections between the ends of the tubes of said bank and said drum, a furnace beneath said bank,-the distance between the source of heated gases and the entrance to said bank being sufliciently high to permit substantially complete combustion before the gases enter said bank,

a row of horizontally-inclined slag screen.

tubes extending across the furnace beneath said bank and widely spaced therefrom and from said Source to provide a large combustion space above and below said row, a. baffle supported on the lower portion of said slag screen tubes, and connections between the ends of the tubes in said row and the drumtoprovide a circulation therethrough independent of the circulation through the main bank. l

16. In combination, a furnace, a row of inclined water tubes extending through the:

furnace walls and across the furnace, tile forming a baffle on the lower ends of the tubes, and tiles extending beneath the tubes near the lower end of the baflle for causing slag to drip from said. baflle before reaching the furnace wall, the gases flowing through said inclined tubes above said tile.

17. A water tube boiler having a bank of I ciently high to permit substantially completecombustion before the gases enter said bank, a plurality of alternately oppositely inclined rows of slag screen tubes extending across the furnace between said source and said bank,

with the high ends of the tubes in one row connected to the low ends of the tubes in the next higher row, connections between the drum and the high ends of the topmost row and the low ends of the lowermost row, and a baflle on each row of slag screen tubes ex-;

tendin from the lowermost ends of the tubes inwar ly partially across the furnace chamher, the tubes in one row being staggered with respect tothose in theother.

18; A water tube boiler having a bank Ofi horizontally-inclined water tubes spaced and the entrance to said hank being? sum DAVID S. JACQBUfi 

